Ultrasensitive non-enzymatic electrochemical detection of paraoxon-ethyl in fruit samples using 2D TiCT/MWCNT-OH.

This study reports on the development of a highly sensitive non-enzymatic electrochemical sensor based on a two-dimensional TiCT/MWCNT-OH nanocomposite for the detection of paraoxon-based pesticide. The synergistic effect between the TiCT nanosheet and the functionalized multi-walled carbon nanotubes enhanced the sensor's conductivity and catalytic activity. The nanocomposite demonstrates superior electrochemical and electroanalytical performance compared to the pristine TiCT and MWCNT-OH in detecting paraoxon-ethyl in fruit samples (green and red grapes), with a linear response range from 0.1 to 100 μM, a low limit of detection (LOD) of 10 nM, limit of quantitation (LOQ) of 70 nM, and sensitivity of 0.957 µA μM cm at pH 8. Furthermore, the sensors maintain excellent selectivity and effectiveness in detecting paraoxon-ethyl even in the presence of various interferents, including diazinon, carbaryl, Fe, NO, NO, ascorbic acid, and glucose. The facile fabrication and enhanced sensing capabilities of the TiCT/MWCNT-OH nanocomposite position it as a reliable, cost-effective, and sustainable alternative to conventional detection systems for monitoring pesticide residues in agricultural products.